[llvm] [SPIRV] Emitting DebugSource, DebugCompileUnit (PR #97558)

[Nathan Gauër via llvm-commits]

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@@ -0,0 +1,208 @@
+#include "MCTargetDesc/SPIRVBaseInfo.h"
+#include "MCTargetDesc/SPIRVMCTargetDesc.h"
+#include "SPIRVGlobalRegistry.h"
+#include "SPIRVRegisterInfo.h"
+#include "SPIRVTargetMachine.h"
+#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineOperand.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/Metadata.h"
+#include "llvm/PassRegistry.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/Path.h"
+
+#define DEBUG_TYPE "spirv-nonsemantic-debug-info"
+
+namespace llvm {
+struct SPIRVEmitNonSemanticDI : public MachineFunctionPass {
+  static char ID;
+  SPIRVTargetMachine *TM;
+  SPIRVEmitNonSemanticDI(SPIRVTargetMachine *TM);
+  SPIRVEmitNonSemanticDI();
+
+  bool runOnMachineFunction(MachineFunction &MF) override;
+
+private:
+  bool IsGlobalDIEmitted = false;
+  bool emitGlobalDI(MachineFunction &MF);
+};
+
+void initializeSPIRVEmitNonSemanticDIPass(PassRegistry &);
+
+FunctionPass *createSPIRVEmitNonSemanticDIPass(SPIRVTargetMachine *TM) {
+  return new SPIRVEmitNonSemanticDI(TM);
+}
+} // namespace llvm
+
+using namespace llvm;
+
+INITIALIZE_PASS(SPIRVEmitNonSemanticDI, DEBUG_TYPE,
+                "SPIRV NonSemantic.Shader.DebugInfo.100 emitter", false, false)
+
+char SPIRVEmitNonSemanticDI::ID = 0;
+
+SPIRVEmitNonSemanticDI::SPIRVEmitNonSemanticDI(SPIRVTargetMachine *TM)
+    : MachineFunctionPass(ID), TM(TM) {
+  initializeSPIRVEmitNonSemanticDIPass(*PassRegistry::getPassRegistry());
+}
+
+SPIRVEmitNonSemanticDI::SPIRVEmitNonSemanticDI() : MachineFunctionPass(ID) {
+  initializeSPIRVEmitNonSemanticDIPass(*PassRegistry::getPassRegistry());
+}
+
+bool SPIRVEmitNonSemanticDI::emitGlobalDI(MachineFunction &MF) {
+  // If this MachineFunction doesn't have any BB repeat procedure
+  // for the next
+  if (MF.begin() == MF.end()) {
+    IsGlobalDIEmitted = false;
+    return false;
+  }
+
+  // Required variables to get from metadata search
+  LLVMContext *Context;
+  std::string FilePath;
+  unsigned SourceLanguage = 0;
+  int64_t DwarfVersion = 0;
+  int64_t DebugInfoVersion = 0;
+
+  // Searching through the Module metadata to find nescessary
+  // information like DwarfVersion or SourceLanguage
+  {
+    const MachineModuleInfo &MMI =
+        getAnalysis<MachineModuleInfoWrapperPass>().getMMI();
+    const Module *M = MMI.getModule();
+    Context = &M->getContext();
+    const NamedMDNode *DbgCu = M->getNamedMetadata("llvm.dbg.cu");
+    if (!DbgCu)
+      return false;
+    for (const auto *Op : DbgCu->operands()) {
+      if (const auto *CompileUnit = dyn_cast<DICompileUnit>(Op)) {
+        DIFile *File = CompileUnit->getFile();
+        FilePath = ((File->getDirectory() + sys::path::get_separator() +
+                     File->getFilename()))
+                       .str();
----------------
Keenuts wrote:

Seems like what you want is:

```cpp
SmallString<128> FilePath;
[...]
FilePath = File->getDirectory();
sys::path::append(FilePath, File->getFilename());
[...]
addStringImm(FilePath, MIB);
```

`append` will handle cases where the LLVM-IR metadata for the directory ends with a trailing '/' while your code doesn't.

https://github.com/llvm/llvm-project/pull/97558